1. Field of the Invention
The present invention relates to an improved method for the angled exposure of at least one surface portion of a substrate to an emission of a source so as to form on the surface portion a layer having selected predetermined properties.
Another aspect of the present invention relates to an improved device in a system for the angled exposure of at least one surface portion of a substrate supported on a substrate holder to an emission of a source impinging obliquely on the surface portion, the device moving the substrate holder so as to improve the uniformity of the emission received on the surface portion.
Still another aspect of the present invention relates to semiconductor wafers having a multiplicity of laser mirror facets formed thereon, parallel to each other and exposed to the emission of a source according to the method of the invention. In an alternative, the present invention relates to semiconductor wafers having two sets of laser mirror facets, each set consisting of a multiplicity of facets formed on the wafer parallel to each other. The facets of the sets are parallel to each other and respectively facing each other and are exposed to the emission of a source independently of each other.
2. Related Art
A variety of deposition and other related exposure methods and systems are known in the art to provide for movement of the substrate holder so as to improve uniformity, thickness, etc. of the resulting surface layers on exposed surfaces. Such known methods and systems have not been specifically developed with a view to perform angled exposure within a closed vessel, and they are not suitable in that they fail to maintain the orientation of the substrate holder with respect to the source while the substrate holder is moved. Further, they do not allow angled exposure to be performed differently on different surfaces of one and the same substrate.
Representative of this known art are the devices disclosed by: L. Nowakowski in IBM Technical Disclosure Bulletin Vol. 29, No. 4 (September 1986) pp. 1805-6, in which the substrate is moved along an orbital path with a superposed planetary movement by means of a driving mechanism comprised of a stationary pinwheel and a sprocket engaging with and orbiting around the pinwheel J. A. Horton and R. P. King in IBM Technical Disclosure Bulletin Vol. 21, No. 6 (November 1978) pp. 2419-20 moves the substrate along an orbital path with a superposed planetary movement by means of a driving mechanism having three revolving parts to provide for a simple relation between the respective angles of rotation for orbital and planetary movement. M. S. Lee in IBM Technical Disclosure Bulletin Vol. 16, No. 9 (February 1974) pp. 2865-8, discusses results obtainable with a system such as this having three revolving parts geared in succession by order of decreasing radii.
None of this prior art however is capable of providing a movement compatible with the angled exposure of laser mirror surfaces of the type disclosed by K. Iga, Y. Mori and Y. Kotaki in Bull. P.M.E. (T.I.T.) No. 58 (September 1986) pp. 17-19 [published by Research Laboratory of Precision Machinery and Electronics, Tokyo Institute of Technology], that is, angled sputtering on each side of a groove etched in a semiconductor wafer. Thus, none of this prior art is capable of improving the uniformity of such angled exposure.